The act of running may be divided functionally into sequences involving heel contact, forefoot contact, heel-off and toe-off functions. The foot pronates on contact with the ground as the leading leg is extended forward. With middle distance and long distance runners, it is usual for the heel to contact the ground first as is true for joggers and walkers. In sprinting, it has been assumed that the runner usually lands on the ball of the foot and the heel seldom contacts the surface. For this reason, presently used track shoes for sprinters have spikes or similar traction devices under the toe and ball portions and have no traction or elevation devices under the heel portion.
Studies have now shown that certain prior assumptions concerning the foot positions during sprinting have been erroneous. By high speed photography, it can be shown that sprinters do make initial contact with the forefoot but then reduce from this elevated position as (1) the propulsive force is exerted by the sprinter and as (2) the fatigue factor increases during the latter stages of the event.
It is the purpose of the present invention to provide a shoe especially adapted for sprinting and running to accommodate the heel-contact phase of the running sequence.